Detection of bad coins



Oct. 19, 1937.

H. L. PETTERSSON DETECTION OF BAD COINS Filed Dec. 17, 1935 7 Sheds-Sheet 1 Oct. 19, 1937. H. L. PETTERSSON DETECTION OF BAD COINS I '7 Sheets-Sheet 2 Filed Dec. 17, 1935 'r sheets-sheets- Filed Dec. 17, 1935 Oct. 19, 1937.

H. PETTERSSON DETECTION OF BAD COINS Filed Dec. 17, 1935 7 Sheets-Sheet 4 Oct. 19, 1937. H. L. PETTER'SSON 2,096,647

DETECTION OF BAD COINS Filed Dec. 17, 1935 7 Sheets-Sheet 6 l i i l@ I l 60 51 TI'" I 94 I I i I f 1 i l 'g; g I 9 6 i Oct. 19, 1937. H. 1.. PETTERSSON 2,095,647

DETECTION OF BAD COINS Filed Dec. 17, 1935 I 7 Sheets-Sheet Patented Oct. 19, 193 7 7 V 2,096,647 f DETECTIONOF BAD COINS Hjalmar Leonard Pettersson, Stockholm, Sweden,

assignor to Patentaktiebolaget Ambia, Stockholm, Sweden Application December 17, 1935, Serial No. 54,893 In Great Britain December 27, 1934 3 Claims. (Cl. 194100) The present invention relates to, and has for in the drawings, a coin chute 3 is provided its object the provision of a novel method of and. through which pass the coins I, 2 to be tested and means for distinguishing between and separately in which are disposed certain detents adapted to disposing of genuine and spurious coins. control the passage of thecoins therethrough and In testing the validity of coins in accordance the locating of the same in testing position. A with the invention, a number of sharpened, yoke 4 is fixed laterally of the coin chute 3 and pointed or edged members are pressed against a swingable bracket 5 is pivoted thereon. In the the coin to be tested with such an adjusted presposition shown in Figure 1 a projection 6 of the sure that when soft metals, for instance lead, bracket 5 extends horizontally through an apertin, type metal, non-alloyed copper or the like, ture l in the coin chute into the path of the coin l0 are encountered the points or edges force their l. The bracket 5 is also provided with another way into and fasten or stick to the coin. so that horizontal projection 8 which extends through the latter becomes held by the points or edges another aperture 9 in the coin chute but does v whereas, on the other hand, when coinsof harder not reach into the path of the coin! in the posimetals or alloys, such as silver, copper or nickel tion shown in Figure 1. The bracket 5 is further 15 alloys, are tested, the points or edges are not provided with a vertical extension is which carable to enter the coin, the result being that, when lies a stud ll extending laterally therefrom at the sharpened members are moved away from right angles to projections 6 and 8. This stud is the testing position, they bring with them coins freely movable inan elongated aperture l2 in of soft metal but leave behind coins of hard a slide l3 which is slidab-ly mounted at M near 20 metal. In this way the spurious coins may be the edge of the coin chute and is provided with distinguished and separated from the genuine a stud l5 extending lengthwise into the coin coins. chute. Between the stud l5 and a quadrangular The invention will be more fully understood projecting arm 6 a spring ll, Figures 2 and 3,

upon reference to the accompanying drawings, is stretched which tends to hold the slide I3 and 5 wherein is illustrated, by way of example only, the stud l5 in their left-hand positions shown in one particular mechanical device for carrying the Figure 1, the stud l5 then projecting into the invention into effect. Various. other objects and path of and supporting acoin'2 in testing position.

features of the invention Will also become appar- The front wall of coin chute3 is provided with ent upon a consideration of the detailed descripa. lateral aperture [8 of a somewhat larger diam- 30 tion of the embodiment thereof which follows. eter than the coins to be tested. The 'chute 3 is Referring now to the drawings, wherein like in direct communication with a chute I9 posireference characters indicate like parts throughtioned for genuine coins and in indirect commuout the several views: nication. through aperture I8 with a chute 20 for Figure l is a vertical section through one form bad or spurious coins. 35 of coin testing device embodying the present in- The testing device proper consists of a slidable vention while Figure 2 is a section through the block-like member 24 on which are mounted a same device but with the parts in other positions, plurality of pointed or edged members such as a portion of the device being shown in full in both. teeth 22, 23 the operative portions of which are 40 figures. formed with such angles and surfaces that, upon 40 Figure 3 is a vertical projection viewed from the points entering into a coin of soft metal, they the line 33 in Figure 1, whereas Figure 4 is a are firmly retained by mea s of f icti n a a nst; vertical projection viewed from the line 44 in and/or adhesion to, the walls of the depressions Figure l. in the coin caused by the entering of the points.

Figure 5 is a vertical projection, and partly a For this purpose the angularities of the surfaces 45 section on the line 5-5 in Figure 7, of an alarm of the coin penetrating portions of teeth 22, 23 or signalling device co-operating with the coin 'With respect to the axes thereof are made less testing device shown in Figures 1 to 4. than the angular limit for frictional immobility Figure 6 is a horizontal section on. the line 6 6 between the material of the teeth and the coin in Figure 5. metal according to the well-known principles for 50 Figure 7 is a vertical projection viewed from a socalled self-locking edge 0 S If points the line l'l in Figure 5. are used they are preferably of conical shape Figure 8 is a circuit diagram of the alarm or with a very acute angle at the vertex as in a signalling mechanism of Figures 5-7. needle. The slide member 24 on which teeth 22,

In the embodiment of the invention illustrated 23 are mounted is provided with a substantially 55 rectangular frame 25 which slides in a suitable guide bracket secured to the front wall of the chute and co-operates with a cam 21 mounted on a rotating shaft 26, rotation of said shaft and cam imparting to the frame 25, the slide 24 and the teeth 22, 23 a reciprocating motion perpendicularly to the flat side of the coin 2 which is held in testing position in the coin chute bystud 15. The shaft 26 may be driven from an electric motor put into operation automatically in a man ner well-known in the art when one or more coins are entered into the slots ofa coin-freed and/or change giving apparatus of which the present testing device is intended to be a part. Said motor may also be started if and when an operator manipulates a member provided for this purpose.

In order to avoid displacement of the coin 2 from the testing position in a direction either perpendicular to or parallel with the path of the testing member 24 during the forward motion of said member, the stud i5 is provided to prevent the coin 2 from falling down while a circular disc 28 is positioned opposite the points 22, 23 to prevent an extended forward movement of the coin. The outer edge of the disc 28 is provided with a flange 29 engaging the rear wall of the coin chute and the disc is loaded on its outside by a pressure spring 30 the compression of which can be adjusted by means of the screw 3| threaded into the yoke 4. The pressure exerted by the spring 36 should be such that the teeth 22, 23 can enter into the metal of coin 2 if it is softer than the pres'cribed'limit, but are prevented therefrom when the coin is made of harder, genuine metal. Such an adjustment is quite easy to attain in practice.

A hole in the slide testing member 24 receives a stud 32 formed on and projecting downwardly from a strike-off member 33 in the shape of a disc. In an annular recess 50 in the slide member 24 is disposed an annular spiral spring or the like 49 which yieldingly pushes a number of pins 48, disposed in radial holes in the slide member, into frictional engagement with the stud 32. The strike-off disc 33 has formed therein openings 34 and 35 which register with the teeth 22, 23. The thickness of the disc 33 is less than the lengths of the teeth 22, 23 so that when the slide member 24 is moved to its extreme lefthand position the teeth 22, 23 reach and engage the coin. At the moment when the teeth 22, 23 first contact the coin there should be a clearance between the rear end surface 36 of the slide member 24 and the strike-oil disc 33 of such an amount that if the coin is spurious the teeth may be sunk deeply enough into the coin metal to adhere firmly thereto. In the case of a genuine coin the teeth cannot enter into the coin metal so that instead the spring-loaded disc 28 is dislocated to the left a corresponding distance.

A gear wheel 31 is mounted on the shaft 26 and meshes with another gear 38 secured to a shaft 39 on whicha cam disc 40 is mounted. The cam disc 40 is provided with a recess 4| which, in the position shown in Figure l, is engaged by a lever 42 pivoted at its lower end on a bracket member fixed to the front wall of the coin chute. The free end of the lever 42 is connected by means of a link 43 with a laterally projecting arm 44 of the swinging bracket 5. A spring 45 tends to hold the lower portion of the bracket 5 in its left-hand position and the upper part "gears 3'! and 38, places shaft 39 in operation. Rotation of the cam disc 40, compare Figure 2,

causes the arm 42 to run up on the cylindrical portion 96 thereof with the result that the link 43 moves the upper end of swinging bracket 5 rearwardly and carries the projection 6 out of the path of the coin I so that the latter is released and drops down. Simultaneously with the swinging out of the projection 6, however, the projection 8 moves into the path of the coin I, catches i the latter and holds it in the position shown in Figure 2. Shortly thereafter the recess 41 again comes opposite the arm 42 so that the projection 8 is moved out of and the projection 6 into the coin path. The coin I held by projection 8 then drops down to the testing position indicated by the character 2 in Figure 1 in which it is supported by the stud I5, while at the same time the projection 6 prevents any further coins I from entering. Simultaneously the cam 21 pushes the frame 25, the slide member 24 and the teeth 22, 23 to the extreme left-hand extreme position. During the next revolution of shaft 26 the operation will proceed according to one of the following two alternatives.

Alternative 1 If the coin is genuine and of a comparatively hard metal so that the teeth 22, 23 cannot enter into the coin metal, the procedure is as follows. During the rotation of the cam 21 to its extreme left-hand position the teeth 22, 23 push the coin and the wall 28 to the left a short distance against the action of the spring 30. Shortly thereafter the cam releases its engagement with the left-hand portion of the frame 25 and engages instead the right-hand portion thereof, as shown in Figure 2, and moves the slide member 24 away from the chute, thereby releasing the teeth 22, 23 from engagement with the coin. At

the same time the arm I0 swings to its extreme right-hand position and carries the pin l5 out of the path of the coin 2, thereby permitting the latter to freely drop down through the chute l9 adapted to receive genuine coins.

Alternative 2 If the coin is spurious and of a comparatively soft metal so that the teeth in their extreme left-hand position enter into and fasten or adhere to the coin metal, the procedure is as follows. The strike-off disc 33 will then be held between the coin 2 and the rear end surface 36 of the slide member 24. During the return motion of the slide, and before reaching the position shown in Figure 2, an abutment surface 46 formed on the disc 33 will come into contact with an abutment surface 41 fixed with respect to the coin chute frame and thereby prevent further forward movement of the strike-oil" member 33 and the coin 2, leaving said member in the position shown in Figure 2. When the slide member 24 continues its return motion to the position shown in Figure 2, the teeth 22, 23 release their engagement with the coin 2 and the latter drops down through the coin chute 26 adapted to receive spurious coins.

The strike-off member 33 will be unnecessary if the coin is instead directly stopped and released from the testing member at a point above the chute 26 by means of a stationary abutment, such as 4'1.

If desired, the chute 20 may communicate with a chute 2| cooperating with an alarm device such as that illustrated in Figures 5 to 8. According to the embodiment illustrated, the front wall of th chute 2i is provided with a lateral aperture 5i into which projects a stop abutment 52 carried by a double-armed lever 53, 54. The lever 53, 54 is pivoted at 55 on a suitable bracket or fixed frame portion 56. Two pairs of spring contacts 5?, 58 and 59, also extend into the opening 5|. These pairs of contacts constitute the legs of U-shaped plates 6| and 62, respectively, which are fixed at their base portions to, but insulated from, the walls of the coin chute 2! in the event that the latter are not insulated per se. An alarm device, such as a bell 63, is mounted on a suitable bracket or frame portion 64. A clapper 65 is pivoted at the point 66 on the same frame portion and carries an arm 61 co-operating with a pawl 66. The clapper 65 is actuated by a spring 84 so that it is normally held out of contact with the bell 63. An electromagnet 15 of horseshoe type tends to attract the clapper 65 to strike the bell. The clapper 65 also carries a circuit breaking contact ll which engages a fixed contact 12 in the inoperative position of the clapper but opens the circuit therethrough in the operative position thereof. Thepawl 68 co-operates with a ratchet wheel 66 in such a manner that the latter is advanced one step in the direction of the arrow in Figme 5 at each reciprocation of the clapper 65. A ratchet 73 for preventing back slippage of the wheel 59 is pivoted at 74 on the frame portion 56. The opposite end of the rachet i3 is jointedly connected with a link '15 the opposite end of which is jointedly connected with the arm 53 at the point '35. On the ratchet wheel is secured a pin T1 so disposed in relation to the arm 54 that the latter projects into the path of the pin. The ratchet wheel also carries an adjustable disc 18 which is secured thereto by screws 16 but may be angularly displaced in relation thereto due to the provision of slots 86 through which the screws extend; On the disc 78 there is also provided a pin 8| co-operating with the arm 54. Ratchet wheel 69 also carries on the side opposite to pin 71 and disc 18 a spring housing 82 containing a spiral spring 83 which tends to rotate said wheel against the direction of the arrow in Figure 5 to the starting position. A leaf spring 86 is provided with a preferably insulatednipple 85 co-operating with a recess inthe arm 54.

The parts are electrically interconnected in the manner shown in Figure 8. From one pole of the current source a circuit may be traced through a series resistance 88, the spring contacts 59, 6B, the coin 6?, the spring contacts 51, 58, the winding of the horeshoe magnet 10, the contacts ll, '42, the clapper 65, the line 89, and the resistance 95 to the opposite pole of the current source. desired, a switch 9| can be adapted to disconnect the resistance 96 so that the'current may pass instead through a signal device or the like interconnected between the terminals 92, 63.

The device functions in the following manner. if and when a spurious coin 8T has been tested and detected and enters the chute 2 i, it is stopped by the abutment 52. In this position a circuit is closed throughthe coin as shown in Figure 8 and the electromagnets 10 are energized and attract the clapper 65. Movement of the clapper against the bell then opens the contacts I I, 12 so that the electromagnet i6 is again de-energized whereupon the clapper 65 is swung back under the action of the spring 84 and the contacts H, 12 are again closed. The clapper 65 is thus given a reciprocating movement so that the bell 63 gives a ringing signal. At the same time the pawl 68 is given a reciprocating motion with the result that the ratchet wheel 59 and its pin iii are advanced stepby-step in the direction of the arrow in Figure 5.

When the pin 8| reaches and actuates the arm 54 the'abutment 52 is moved outwardly from beneath the coin 81, carrying with it a cross rod 94. The rod 9 raises the spring contacts 56 and 60 which in turn, through the intermedium of an insulating rod 95 fixed to the contacts 57, 53, raise the latter out of engagement with the coin Bl. At the same time the nipple 85 drops into the recess 86 so that the arm 53 is held in this position for a short moment. The coin may then drop down freely and continue its passage through chute 2| to its ultimate destination. As soon as the arm 53 has taken up its swung-out position the link 15 holds the ratchet 13 out of engagement with the ratchet teeth of the wheel 69. Then when the pawl 68 slides out of engagement with the teeth at the next oscillation of the clapper 65 the wheel 69 will be released and rotate under the action of the spring 83 against the direction of the arrow back to its normal at rest or starting position As the ratchet wheel approaches its starting position the pin 71' will actuate the arm 54 so as to return itto the position shown in Figure 5, in which position the abutment 52 is in the path of and ready to retain the nextcoin entering the chute, and the springs 5'l, 5i! and 59, 5B

are in position to contact therewith. At the same time the ratchet 53 again takes up an operative position in relation to the ratchet wheel 59'and the device is ready to give a signal if and when the next spurious coin is inserted in the apparatus. V r

If desired, the alarm device may be disposed at a distance from the testing apparatus, as in a watchroom' or in the localities of the police force or the like. It may also be adapted to actuate a lamp or other visual or acoustic signal.

It is to be understood that the embodiment of the invention disclosed herein is for purposes of illustration only and is not to be construed as defining thelimits of the invention. For example, various changes, substituticns and modifications which will now become apparent to those skilled in the art may be made in the form, details of construction and arrangement of the parts without departing from the spirit of the in' vention. Reference is therefore to be had to the appended claims for a definition of the limits of the invention. I

What is claimed is:--

1. In a coin testing device for distinguishing between and separately disposing of genuine coins and spurious coins made of a metal softer than that of the genuine coins, means for holding the coins to be tested in testing position, a testing member having mounted thereon a plurality of elements having sharpened portions adapted to engage the coins, means for moving said test ing member toward and away from the coin testing position so as to bring said sharpened elements into contact with'the coins, yieldable means for limiting the pressure exerted by said elements against the coins to an amount insufiicient to effect penetration thereby of a genuine coin, said pressure being such and the sharpened portions of said elements having such angles and surfaces of engagement with the coins that upon contact with a spurious coin of soft metal said sharpened portions are forced into the coin in such manner that the latter becomes adherent thereto, a strike-off member interposed between the testing member and the coin testing position and having openings therein through which the sharpened portions of said elements may extend for engagement with the coins, said strike-off member being movable with said testing member toward and away from the testing position, and means for limiting the extent of movement of said strike-off member away from the testing position to an amount less than that of said testing member whereby continued movement of the latter after said strike-off member has reached the limit of its movement releases the adherence between said sharpened elements and any spurious coin that may be engaged thereby.

2. In a coin testing device for distinguishing between and separately disposing of genuine coins and spurious coins made of a metal softer than that of the genuine coins, means for holding the coins to be tested in testing position, a testing member having mounted thereon a plurality of elements having sharpened portions adapted to engage the coins, means for moving said testing member toward and away from the coin testing position so as to bring said sharpened elements into contact with the coins, yieldable means for limiting the pressure exerted by said elements against the coins to an amount insufiicient to effect penetration thereby of a genuine coin, said pressure being such and the sharpened portions of said elements having such angles and surfaces of engagement with the coins that upon contact with a spurious coin of soft metal said sharpened portions are forced into the coin in such manner that the latter becomes adherent thereto, a strike-01f member interposed between the testing member and, the coin testing position and having openings therein through which the sharpened portions of said elements may extend for engagement with the coins, means providing a frictional connection between said strikeofi member and said testing member whereby said members normally move together toward and away from the testing position but are capable of relative movement with respect to one another, and means for limiting the extent of movement of said strike-off member away from the testing position to an amount less than that of said testing member whereby continued movement of the latter after said strike-01f member has reached the limit of its movement releases the adherence between said sharpened elements and any spurious coin that may be engaged thereby.

3. In a coin testing device for distinguishing between and separately disposing of genuine coins and spurious coins made of a metal softer than that of the genuine coins, a coin chute for the coins to be tested having opposite walls parallel to the flat faces of the coins, means for temporarily holding coins in testing position at a point within said chute, a testing member having mounted thereon a plurality of elements having sharpened portions adapted to engage the coins, means for moving said testing member toward and away from the coin testing position in a direction perpendicular to the walls of said chute so as to bring said sharpened elements into contact with the coins, one of the walls of said chute having an opening therein adjacent the coin testing position through which said sharpened elements are moved, the opposite wall having an outwardly movable section of greater area than that of the coins to be tested, and spring means for yieldingly resisting movement of said movable section, the pressure exerted by said spring means beingso adjusted as to limit the pressure exerted by said elements against the coins to an amount insufiicient to effect penetration thereby of a genuine coin, said pressure being such and the sharpened portions of said elements having such angles and surfaces of engagement with the coins that upon contact with a spurious coin' of soft metal said sharpened portions are forced into the coin in such manner that the latter becomes and remains adherent thereto until forcibly removed therefrom.

HJALMAR LEONARD PETTERSSON. 

